April, ’23] 
flint: SAN JOSE SCALE CONTROL 
209 
December first. These adults were found resting upon window screens 
all through the fall months. Frequently we have counted as many as 
fifteen adults on a single screen covering half of the window of the 
Entomological Laboratory at the Station. Dr. Porter reports that he 
counted thirty on one screen at Wallingford, Conn. 
From the available life history data, published and unpublished, it 
is apparent that the winter is passed by this insect in the adult stage, 
though possibly an occasional pupa may live through the winter. It is 
also evident that the spread of the species takes place chiefly by the 
adults emerging in abundance and moving in the direction of the prevail¬ 
ing winds. 
Mr. S. W. Frost: I am especially interested in this pest and in the 
way it has migrated to the East. I have been on the watch for this 
pest but have not seen anything of it to date in the southern part of 
Pennsylvania. In the northern part of the state I have not traveled so 
much and have not been able to make many observations. 
I might say that I have seen outbreaks along the Hudson River and it is 
rather a striking pest—green with relatively large black spots and it would 
be very difficult to overlook it. I feel very certain that the pest has 
not occurred in Pennsylvania and I would be interested to know if any¬ 
one has found it in New Jersey or in the northern part of Pennsylvania. 
Mr. W. E. Britton: Dr. Felt has told me that this insect occurs in 
the Hudson Valley as far north as Albany, but apparently has spread 
only four or five miles each side of the river. The sprayed orchards 
were not injured. 
President J. G. Sanders: The next paper is by Mr. W. P. Flint. 
SHALL WE CHANGE OUR RECOMMENDATIONS FOR SAN 
JOSE SCALE CONTROL 
By W. P. Flint, Urbana, III. 
Abstract 
During the years of 1920 to 1922 inclusive, the San Jose Scale, Aspidiotus per - 
niciosus , has increased very rapidly in southern Illinois and neighboring states. In 
southern Illinois it has resulted in the loss of over one thousand acres of commercial 
orchard annually treated with lime sulphur. 
Experimental work was carried out in the spring of 1922 with miscible oil and 
lubricating oil emulsion, similar to those used by the Federal Bureau of Entomology 
in Florida. The lubricating oil emulsion gave nearly as good control of the scale as 
did the miscible oil and a much higher degree of control than was obtained from 
